Hi STBT
I sympathise hugely as I've been going through similar dental problems for as long as you... I posted on here a while back and was -very- grateful for the help I received.
Brief summary - since December... 2 problem teeth (bottom left molars), dressing fillings, then root canals, then retreatments of root canals... took months for each tooth, with loads of different antibiotics for each, and a shedload of painkillers. Not funny. Both teeth eventually extracted, one in March, the other a couple of weeks ago, which was the last thing I wanted at the beginning of the process, but by the end of the saga with both they could have taken off my head! No teeth remaining bottom left. Horrible.
I'm thinking of marketing the 'root canal diet' as I've lost 14lbs....!
I am in now exactly the same position as you.... very sore jaw and -very- sore teeth - as in wake up at 3am with sore teeth sore! And, like you, my whole mouth hurts - and hurts badly.
For me, the above troubles have been diagnosed as caused by grinding at night which I have been doing for many years, but with all this dental work I am apparently now doing it worse and differently. I therefore worry about grinding when I go to sleep, as I certainly would NOT want to go through all the above again and crack and lose any more teeth, so I think that makes it worse. I now seem to grind and clank and crash my teeth in the most strange way ever and wake myself up doing it!
Thankfully, my new dentist is making me a new guard which I get middle of next week which I so hope will sort all this out.
I had a NTI guard (from my old dentist) which I'd been using religiously but it has now been said this has been the cause of my troubles rather than the cure for them as I had thought when I spent lots of dosh on the wretched thing a number of years ago.
My bite, like yours, is well off and I will be very, very grateful if this new guard is the answer. I will certainly let you know if it cures the jaw, teeth and mouth pain.
MC